The task was to remove a menu item from the admin menu. I tried to do it through roles permissions but it wasn't saving permission for few selected custom modules. So, I had to leave it as 'All' as i didn't wanted to waste time researching and fixing other custom modules.
I removed menu items from menu node in config.xml but it didn't work. Deleted cache folder, session folder nothing worked. After googling for a while I found people recommended to do it through javascript by adding display none to the item like this: